P0420

2005 SATURN ION
156,000 MILES • 2.2L • 4 CYL • 2WD • AUTOMATIC
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FYRECHILDE
  • MEMBER
  • 1 POST
Engine light came on. We get two codes, both showing P0420. Since this code came up twice, does this mean that the catalytic converter needs to be replaced? Or should I try replacing the downstream oxygen sensor first?
Mar 12, 2016 at 10:21 AM
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CJ MEDEVAC
  • ASE Certified Mechanic
  • 11,004 POSTS
  • ASE Certified Mechanic
THE EZist THING TO TRY IS RUN A FULL BOTTLE OF "SEAFOAM" IN YOUR GAS TANK. THIS WILL HURT NUTHIN' (EVEN IF IT DOES NOT WORK) BUT MANY TIMES THIS WILL FIX MANY O2 ISSUES.

HAVE YOU A LINK BELOW OF THE PRODUCT, OTHER STORES HAVE IT TOO

http://shop.advanceautoparts.com/p/sea-foam-motor-treatment-for-gas-and-diesel-engines-16-fl.-oz.-sf16/6410004-P?searchTerm=seafoam

LET US KNOW HOW IT GOES

THE MEDIC
Mar 12, 2016 at 4:36 PM
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